dynamic_debug: change verbosity at runtime

Allow changing dynamic_debug verbosity at run-time, to ease debugging
of ddebug queries as you add them, improving usability.

at boot time: dynamic_debug.verbose=1
at runtime:
root@voyage:~# echo 1 > /sys/module/dynamic_debug/parameters/verbose

Signed-off-by: Jim Cromie <jim.cromie@gmail.com>
Signed-off-by: Jason Baron <jbaron@redhat.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
diff --git a/lib/dynamic_debug.c b/lib/dynamic_debug.c
index 416c079..8c88b89 100644
--- a/lib/dynamic_debug.c
+++ b/lib/dynamic_debug.c
@@ -60,6 +60,7 @@
 static DEFINE_MUTEX(ddebug_lock);
 static LIST_HEAD(ddebug_tables);
 static int verbose = 0;
+module_param(verbose, int, 0644);
 
 /* Return the last part of a pathname */
 static inline const char *basename(const char *path)